LOCal Oxidation of Silicon (LOCOS) is a microfabrication process where silicon dioxide is formed in selected areas on a silicon wafer having an Si—SiO2 interface. The current process of record for a contact structure of a LOCOS deep trench isolation (DTI) requires an etching process through the LOCOS oxide. This etching process cannot be achieved without an additional mask to define the contact etch through the LOCOS oxide on a doped poly of DTI. This is a costly process and adds to the manufacturing complexity.